Stability of PVC polymerization temperature control
Thread Content
In PVC polymerization production, the stability of temperature control in the polymerization reactor plays a crucial role in product quality. How to establish a temperature control model to achieve satisfactory temperature control is a matter of great concern for those involved in PVC production. One is the issue of a smooth temperature transition at the beginning of polymerization, that is, after all the materials have been added to the polymerization reactor, how quickly can the reactor temperature reach the controlled temperature within the shortest possible time (10 minutes or 5 minutes)? Second, during the normal polymerization reaction, how can the reactor temperature be maintained within a fluctuation range of plus or minus 0.2°C (or even plus or minus 0.1°C), and how can the jacket temperature or water flow rate remain on a continuous curve rather than showing intermittent fluctuations [with fluctuations within a certain limit, such as 5°C]?
The temperature of the hot water feed is controlled at around 75-80 degrees; before adding the initiator, circulating water cooling is initiated based on experience, and by the time the polymerization feed is complete, the temperature has almost reached the desired level. During the reaction process, control is generally achieved by using the water in the jacket under a cascade control system; with an appropriate amount of initiator used, the temperature increase should not be significant. If the temperature rise exceeds 0.5–1 degree, an appropriate amount of terminator should be added
Controlling the reactor temperature is highly laggy, with large fluctuations over time. The on-site operator is watching constantly, and the cascade control cannot be activated. Do you experience this phenomenon?